116 lines
4.6 KiB
HTML
116 lines
4.6 KiB
HTML
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<!DOCTYPE html PUBLIC "-//w3c//dtd html 4.0 transitional//en">
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<html>
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<head>
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<meta http-equiv="Content-Type" content="text/html;
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charset=windows-1252">
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<meta name="GENERATOR" content="Mozilla/4.7 [en] (X11; U; OSF1 V4.0
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alpha) [Netscape]">
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<meta name="Author" content="C. L. Davis">
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<title>Light and Optics - Brewster's Law - Physics 299</title>
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</head>
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<body style="color: rgb(0, 0, 0); background-color: rgb(255, 255,
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255);" link="#0000ee" bgcolor="#ff0000" text="#000000"
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vlink="#551a8b" alink="#ff0000">
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<center>
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<h1><img src="ULPhys1.gif" height="50" width="189" align="texttop">
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</h1>
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</center>
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<center>
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<h1>Brewster's Law<br>
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</h1>
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</center>
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<center><img src="celticbar.gif" height="22" width="576"> <br>
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<br>
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<font color="#ff0000"><i>"</i><i><span></span></i><i>If aliens
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visit us, the outcome would be much as when Columbus landed in
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America, which didn't turn out well for the Native Americans.</i><i><span></span></i><i>"</i></font><br>
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<font color="#ff0000"><i>
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<meta http-equiv="content-type" content="text/html;
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charset=windows-1252">
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</i></font><font color="#ff0000"><i>
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<meta http-equiv="content-type" content="text/html;
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charset=windows-1252">
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</i></font> Stephen Hawking<br>
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<br>
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</center>
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<img src="netbar.gif" height="40" width="100%" align="middle"> <br>
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<br>
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<ul>
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<li>By applying the boundary conditions for electromagnetic waves
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striking the boundary between two media it can be shown that the
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intensity of the reflected and refracted waves depend on the
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polarisation of the incident wave. <br>
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</li>
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</ul>
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<ul>
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<li>In particular, for unpolarised light incident on the boundary
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at a specific angle, θ<sub>p</sub> , the reflected light
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contains only one polarisation. When this occurs the
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reflected and refracted light rays are at 90<sup>0</sup> to each
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other, <br>
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</li>
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</ul>
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<div align="center"><img alt="brewster eqn1"
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src="lo_brewster_eqn1.jpg" height="58" width="156"><br>
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<div align="left">
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<ul>
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<li>Using Snell's law we can show that,</li>
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</ul>
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<div align="center"><img alt="brewster eqn2"
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src="lo_brewster_eqn2.jpg" height="86" width="390"><br>
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<blockquote>
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<div align="left">This relationship is known as <a
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href="http://www.brewstersociety.com/brewster_bio.html"><img
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alt="brewster" src="lo_brewster.jpg" height="128"
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border="0" width="108" align="middle"></a><a
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href="http://www.brewstersociety.com/kaleidoscope-university/sir-david-brewster/">Brewster's
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</a> Law.<br>
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<br>
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<div align="center"><img alt="brewsters fig1"
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src="lo_brewster_fig1.jpg" height="297" width="405"><br>
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</div>
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</div>
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</blockquote>
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<div align="left">
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<ul>
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<li>For light incident on water (from air) we find that θ<sub>p</sub>=
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53<sup>0</sup>. Thus, at this angle the light
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reflected from the surface is (linearly)
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polarised. If this reflected wave is viewed with
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polarised sunglasses (which block this particular
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polarisation), no reflective glare is observed -
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allowing the observer to see clearly underwater.<br>
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</li>
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</ul>
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</div>
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</div>
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</div>
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</div>
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<ul>
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</ul>
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<br>
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<img src="netbar.gif" height="40" width="100%"><br>
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<center>"<font color="#ff0000"><i><span class="bqQuoteLink">Outside
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of a dog, a book is a man's best friend. Inside of a dog
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it's too dark to read.</span></i><span></span><span
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style="font-style: italic;">"</span></font><br>
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<span style="font-style: italic; color: rgb(255, 0, 0);">
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<meta http-equiv="content-type" content="text/html;
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charset=windows-1252">
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</span> Groucho Marx<br>
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<br>
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<img src="celticbar.gif" height="22" width="576"> <br>
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<p><i>Dr. C. L. Davis</i><br>
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<i>Physics Department</i><br>
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<i>University of Louisville</i><br>
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<i>email</i>: <a href="mailto:c.l.davis@louisville.edu">c.l.davis@louisville.edu</a>
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<br>
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</p>
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<p><img src="header-index.gif" height="51" width="92"> </p>
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</center>
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<p><br>
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</p>
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</body>
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</html>
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